The Oceans. Advanced

In this Advanced section on The Oceans, we will look at predictions of how global warming will change sea level and ocean circulation and how this is likely to further affect the climate of the Earth. We will also look at the North Atlantic Oscillation, a natural weather pattern, which controls whether winters in Europe are warm and wet or sunny and dry. We will also discuss why large areas of the oceans have lots of nutrients but little phytoplankton growth, concentrating on the importance of iron as a micronutrient. Finally we will look at how gases from phytoplankton enter the atmosphere and introduce the concept of climate feedback loops.

1. Oceans and climate

We know that the oceans are a really important part of the Earth's climate control system. We don't know, though, how ocean circulation is likely to change as a result of global warming. We don't know either whether natural weather patterns such as the North Atlantic Oscillation, which influence wither time climate in Europe, will be altered by global warming.

In this unit we look at the predictions of up-to-date computer models of ocean circulation and see how global warming is likely to affect the oceans and therefore the climate of our Earth.

2. Oceanic nutrients - Iron

In large areas of the ocean there are plenty of the nutrients nitrogen and phosphorous but not many phytoplankton. One of the biggest discoveries in oceanography over the past few decades has been that concentrations of iron in some ocean waters are lower than the levels that phytoplankton need to grow. In this unit we look at the importance of iron in the oceans and why iron is important to our climate. We also look at the pros and cons of deliberate large scale open ocean iron fertilisation and whether this could solve our global warming problems.

3. Gases from phytoplankton

The impact of carbon dioxide on our climate depends on how much of the gas is in our atmosphere. About a third of the carbon dioxide we produce from fossil fuel buring is stored in the oceans, greatly reducing the impact of global warming. In this unit we look at how the carbon dioxide enters seawater. We also look at how climatically important gases such as dimethyl sulphide, which are formed in the oceans, leave seawater and enter the air. We also look at the suggestion made by Jim Lovelock in the 1960's that the Earth is a self regulating system that acts to keep our planet a fit place for life and show one example of how this may happen. He called this system GAIA after the Greek Goddess of the Earth.